a) Field of the Invention
The present invention relates to a performance improved spectacle-mounted display apparatus using a concave surface of a spectacle lens as a primary reflector wherein the improvement comprises the addition of a movable relay mirror mounting assembly possessing a bracket whose translational movement causes framing adjustments and a change in the distance of the relay mirror from the object.
b) Description of the Prior Art
Objects viewed through a magnification system require a set of adjustments of the optical train to ensure satisfying the following conditions: (1) focus control and image placementxe2x80x94the image is resolute and a specified distance from the viewer, (2) framing of the image within the viewing areaxe2x80x94the entire image is in view, and (3) image alignment/orientationxe2x80x94the image is without geometrical distortion.
The use of an optical eyepiece consisting of mirrors on two or more axes for personal display of optical information, wherein a portion of the spectacle lens is used as a concave primary reflector, is known. Bettinger, U.S. Pat. No. 4,806,011, uses the cavity between the spectacle lens and the eye to position the basic elements of a magnification system for the purpose of developing a portable, lightweight, inexpensive personal optical system. The key feature of Bettinger is the use of a section of the concave surface of the spectacle lens as a primary reflector. Bettinger allows for focus adjustment only by selection of S different curvatures of the mirrors. Bettinger allows for alignment/orientation of the image by bending or manipulation of a flexible relay mirror support arm. Bettinger does not provide a means for adjusting image location and focus control by changing the distance between the elements of the optical system. Bettinger does not provide a means for vertical movement of the relay mirror in order to align the center of the relay mirror at the same vertical height with the center of the eye.
In the prior art, it has been found that small adjustments of the relay mirror may cause substantial changes in the image in terms of location and framing. In order to overcome the above-mentioned deficiencies and problems with respect to the ability to make precise adjustments in the prior art, this invention teaches a novel spectacle-mounted ocular display apparatus, the performance improvements enhancing image quality and adjustment. One performance improvement comprising the addition of a movable relay mirror mounting assembly provides aid for image focusing and placement, framing, and orientation/alignment by permitting translational and rotational movement of the relay mirror.
More specifically this movable relay mirror mounting assembly comprises
a) at least two continuous contact tracks integral with, and in close proximity and attached to, the spectacle frame in a generally parallel relation to an extension of the image path that crosses the facial cavity of the eye, and
b) a bracket with runner means of engaging and maintaining at least three contact points with at least two of the contact tracks, furthermore the bracket integral with, and in close proximity and attached to, the relay mirror support arm at the end opposing the relay mirror,
c) whereby translational movement of the bracket along the length of the tracks causes a change in the distance of the relay mirror from the object which in turn causes both an optical change in the distance of the image from the eye and a change in control of image focus quality.
The addition of a vertical adjustment control assembly, for relay mirror vertical displacement, connects the horizontally moveable bracket to the relay mirror support arm and furthermore the vertical adjustment control assembly comprises
a) at least two continuous contact tracks integral with, and in close proximity and attached to, the bracket in a generally perpendicular relation to the image path that crosses the facial cavity of the eye, and
b) a vertical adjustment control with runner means of engaging and maintaining at least three contact points with at least two of the contact tracks,
c) whereby translational movement of the vertical adjustment control along the length of the tracks causes vertical movement of the relay mirror providing the means to aid in the avoidance of image skewing and distortion.
The addition of a setscrew adjustable and controllable hinge connecting the horizontal translation retainer to the relay mirror support arm provides for the change in relay mirror angle relative to the primary mirror providing assistance for the fine framing adjustment of the object.
Another performance improvement comprises the addition of an elastic pivot and hinge, selected to be adjustable and controllable by precision means, which connects the relay mirror support arm to the relay mirror. This provides for a change in relay mirror angle relative to the primary mirror providing assistance for fine framing adjustment of the object.
The precision means of adjusting and controlling this hinge is accomplished by a thumbscrew circular wedge, a setscrew, or other such appropriate precision means.
A general object of this invention is to provide for the adjustment in the distance of the image plane from the viewer. For example, a worker at a computer workstation will desire the plane of the virtual image to be at the same perceived distance as the desktop display of between 24 to 30 inches.
Another general object of this invention is to provide for a more precise adjustment of focus.
A still further object of this invention is to provide for a more precise horizontal adjustment for framing of the image within the viewing area.
A still further object of this invention is to provide for a more precise vertical adjustment for framing of the image within the viewing area.
A still further object of this invention is to provide for image focusing so as to accommodate variations in individual visual capability with standard glasses.
In keeping with these objects and others that will become apparent hereinafter, one feature of the present invention resides, briefly stated, in the movable relay mirror mounting assembly that permits the translational movement of the relay mirror relative to the spectacle frame. This provides the spectacle wearer with the ability to focus and adjust placement of the image.
An additional feature of the present invention resides in the vertical adjustment control assembly whose continuous contact tracks permit the vertical translational movement of the relay mirror relative to the spectacle frame. Precise control of a small vertical displacement cannot be accomplished by a mere bending of the support arm.
A further feature of the present invention resides in the setscrew adjustable and controllable hinge connecting the horizontal translation retainer and the relay mirror support arm. This setscrew hinge provides a means of fine adjustment of the relay mirror angle relative to the primary mirror. Precise horizontal adjustments for framing of the image cannot be accomplished by a mere bending of the support arm.
A still further feature of the present invention resides in the precision thumbscrew adjustable and controllable hinge connecting the relay mirror support arm and the relay mirror. This wedge wheel feature provides a means of fine horizontal adjustment of the relay mirror angle relative to the primary mirror. This ability to achieve fine framing of the image can""t be accomplished by a mere manipulation of a flexible support arm.
It will be understood by one of ordinary skill in the art that horizontal alignment of the optical plane may require vertical adjustment of the image source, in addition to vertical adjustment of the relay mirror.
It will be additionally understood by one of ordinary skill in the art that a distortion free image may require adjustments to vertically orient the image source parallel with the sagittal plane.
It will be further understood by one of ordinary skill in the art that adjustments of the object may be required to achieve proper framing.
It will be still further understood by one of ordinary skill in the art that an individual""s deviation of visual acuity may be greater than that which could be accommodated by translational adjustment alone of the present invention and a different lens curvature may be required.
It will be still further understood by one of ordinary skill in the art that the horizontal contact tracks may be shaped to generate a locus of motion of the relay mirror to proscribe a change in angle relative to the primary lens that maintains the axis of the image line centered on the relay mirror.
It will be still further understood by one of ordinary skill in the art that the connection of the continuous contact tracks to the spectacle frame may be selected to provide for a temporary connection of the relay mirror mounting assembly to the spectacle frame for purposes of safety and convenience during storage and transport.
It will be still further understood by one of ordinary skill in the art that the translational movement of the horizontally movable bracket along the length of its tracks causes a change in the distance of the relay mirror from the object which may serve to cause both an optical change in the distance of the image from the eye and a change in image focus quality where the preferred plane of focus of the eye is different than the perceived image plane of the personal display.
Numerous alterations of the mechanisms of precise image adjustments herein discussed will suggest themselves to those skilled in the art. However it is understood that the present disclosure of these mechanisms are for purposes of illustration only and not to be construed as a limitation of the present invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims.